Lubrication of gears and the like



Patented Nov. 17, 1931 lED.STATESg PATENT OFFICE i :FRANK r. DAHLSTROM, or WORCESTER, MASSACHUSETTS, AssIeNOR To MORGAN CONSTRUCTION COMPANY, or WORCESTER, MASSACHUSETTSA CORTJORATION or MASSACHUSETTS ILUBRICA'TION or GRARS ANDy THE LiKE Application mea March 2o, 1929'. seriai No. 348,502.

The present invention relates in general to the lubrication of gears, or similar rotary elements.

I It is customary, in the case of a vertically 5' disposed gear, to secure its lubrication Vby partial submergence of the saine in a liquid or semi-liquid lubricant Contained inthe gear box or casing. If'the lubricant appreciably submerges such a gear, excessive churning is almost Certain to occur, which raises the temperature of the lubricant and reduces correspondingly its lubricating properties. Not only that, but' the lubricantacts as a very powerful brake on the rotating gear andvery materially' reduces thepower which is lto be transmitted thereby, and also the speed at which the gear can run. z

' In the operation of large high speed gears, to avoid the churning lof and brakingV by thelubricant, it is the custom to keep the lubricant level so low in the gear case that only a very slight submergence of the gears periphery is obtained. This slight submergl, ence serves the purpose very well with or- 2.dinary spur gears, because the teeth 'O such gears, lying wholly on the outs1derim, or portion of greatest' circumference, are successively'.- carried almost completely below the lubricant level, even with a very slight eripheral submergence of the gear body.

lllVith bevel gearing however, a C lifferent situation-exists. The teethl of a bevel gear are cut on the face rather than on the periphery of the disk, and they extend radially inward toward the center for an appreciable distance, so that when the customary'slight peripheral submergence is arranged for, only the outer tips of the bevel gear teeth willl dip below the level of the lubricant. In-otherwords, the same slight peripheral -submergence (limited soas to avoid churning'and braking effects) that puts .a film of lubricant over the entire tooth surfaces of spur gears, Cannot possibly serve tofadequately lubricate the entire surfaces of vbevel Y gear teeth; because such bevel toothrsurfaces, for the major portions of their areas, inwardly of the extreme outer-tips of the r teeth, would be practically untouched by the Jo'lubricant. Y .c

`a larger scale, illustrating the action of the device.; c

According to this invention, the above mentioned diicultiesin the` lubricationv of bevel gears and the like are overcome', "in the absence of: any deeper submergence lof the gear teeth in the lubricant', by the provisionof Yadevice which utilizes the motion of the. teeth ythemselves to secure the spreadingof the lubricant over the entirefunsub- :merged: portion of-each. tooth. Other and further objects and advantages of the invention willbe apparent from the following detailed description thereof, taken in connection with the accompanying illustrative drawings in which.- y

' F ig. l is an elevational view, partly in section, `showing my` invention applied to the lubrication of bevel gears.

Fig. 2 shows the same' parts, as viewed fromy va'plane at right angles to that, of Fig; l.v v

3 is-a fragmentary isometric view on v Like reference characters, refer to like parts the `different gures. v In said drawings, the numeral 1 indicates the usual. gear box or casing for a pair of vintermeshing bevelgears 2 and v3,one of which (in thislcase the gear 2)l runs with itsv lowest point submerged below the level 4 of liquid lubricantk contained in the casing l. As shown, the teeth 5 of gear as they successively :reachthe lowest posit-ion, only dip their extreme outer portions below .the

`lubricant level4, thus avoiding such a submergence ofthe gear body `as would cause undue churning of the' lubricant and afbraking effect on the gear. That isto say, any

appreciable raisingof thelubricant level 4, by the introduction Ofmore lubricant to the lcasing l, would produce objectionable churning and braking eifects' in the operation of the gear 2; on'the other hand, 'it is evident that,

under the conditions illustrated, there would ordinarily be no adequate lubrication of the inner unsubmerged portionsfof the gear teeth v5, or of the corresponding toothportions of thelintermeshing gear 3, since only the outer tips of the; teeth 5 dip below the lubricant level 4.

n cent said teeth, conforms substantially to said gear surface, Without actually touching This situation is corrected by the device of my invention, which comprises a stationary partially-submerged member or blade 6, having a suitable mounting, as shown at 7, in the zone ojsubmergence of the gear teeth 5. Said meiiiberor blade 6 is inclined from the vertical in the direction of travel of the teeth (shovvnby arrow A) and its surface, so inclined, lies/in aplane Which makes an acute anglei'vvitli the surface traced by the acesof teeth 5. The inner edge 8 of blade 6, adjasame, and thus the bladesurf-,ace andthe gear surface cooperate to Aform a sloping wedgeshaped'trough, the upper .portion .of which is above the lubricant level 4...

i :Theaction ofthe .stationary blade V6, ar-

. ranged as iabove describedpiponthe 'heavy lubricating materialiset in motion by the ro.- tatinggear 2,*may be' compare'd to thatof a plow, similarly arranged and moving through the niaterialfrom left to right in' Fig. 2. Just as such a'plovvl would rvdeiect the material, cumulatively, .toward its outer end, sothe blade y6,-standing'as an obstructionfto the lubricant. set .in-motion by the sweepfoitlie [successive gear teeth. 5 therethrough, .causes said lubricant to climb upwardly, Wellabove g i the levelli,y in the inclined trough which is formed with the .gear face.` Thus, the lunsubmerged or inner portions of the teeth 5, as

4theyfsvveep past Ythe blade 6, `vvi-ll acquire an Vadequate coatingv of lubricant, by'their con'- tact with the constantly maintained 'sup-plyof lubricant inthe unsubine-rged portion of said trough. ln other Words,notwithstanding the fact that the lubricant level 4l is kept -soV lorsT that it isreachedonly by the extreme kouter tips of the teeth 5, myinvention-secures, in the jabsence of undue llubricant churnings,` or

braking effect on the gear, an elevation and spreading of thelubricant onto-:the inner. .unsubmerged portions of the gear teeth'us f' 3: they sweep past the member 6. Y

From the foregoing, itis apparent .that the presen-t invention provides-anextremely eiec- "tive means for spreading -tlielubricant over the entire face of a rotating gear, the device Yfunctioning invariably to bring about this result, without .requiring any deeper submerg-encefof the teeth. The deviceis charact'erized by its extreme simplicity and the tact that When-once installed itWill operate continuously, Without requiring, any adjust- .mentsg and since there areno parts subject to Wear, the device is adaptedto successfully perform its function indefinitely. Y

- I claim.: Y n l p l, The combination, with rotating -ele- .nient providing an annularfae Whose lower portion has limited submergence'inliquidfluybricalnt, ofa cooperating stationary member for spreading the lubricant set in motion'zby Lesacee' nular :face nearer tov the axis of said rotating element.

y 3, The combination, with a gear having tooth faces'radiating from its axis, Whose rotation sweepsithe outer portions `only `ofits tootliitacesthroiigh-a liquid lubricant supply, of a stationarymember cooperating Withlsald gear to .ob-,tain .thev elevation of lubricant to the other nner portionsfo'f said toothy faces,

...4, 'The combination, with a gear having roothi-aces radiating from its axis, Whose rolf tation ,sweeps :the @libel-*ends only. o fits teeth farthest removed `troni. the` gear laXS-i fhrelvl-Jh a liquid ,lubricant supply, of .a stationary membercooperating with' ksaid gear4 to obtain the elevation .of lubricantto the other., inner pcrtonsof said teeth vnearerttm gear axis,

said member being partially submerged in.

sairllnbricant-supply, y.

.5.- Therombinatoa with, a bevel. gear, Whose rotation sweeps the. outer ends only of itsiteeththrough @liquid `lubrica/nt supply, Q afstatonaryzmember cooperating wthsad Y gear-to nbtaii the elevation of lubricant. to the 'l ntheninnerportons of sadteeth, said memfber presenting .to-the lubricant set in motion by said gear, .a surface that makesan acute anglewithtlieface of said geard `whose -retationsweeps .the .outer ends only. of its teeth through .a .liquid lubricant supply, of ,a stationary member sGQOplLlIlg 'With .Said gearito obtain .the :elevaiQIl Lof lubrieantito ,the `other, inner Yportioifi koil-.said teeth, saidmemben roep erating with lthe vface .ofl s aid gear. to; provide `i111,.lililed Wl'ge Shhpd trough, forjtlie conveyanceof l-ubricantsj set in motiony bysaldggear.

'Y V7. The .combination wlth-a bevel geen Awhnse rotationsweeps the Outer ends only. of its vteeth through. a liquid lubricant -s-iipply, of .astatonary member cooperating 'Withzsaid gear to obtain the ,ielevatn .of lubricant gto .the other, inner port-ions of. said teeth,.said member f icooperating .with :the .tace 'f Q .Said

gear .to provide aivedge shaped trough, in- @lined inztilie direction of Vmovement nf the gear.,teeth through saidlilbricallt.

8. Y The nomination, VWit-li a rotating leiii-ent presenting an :annular .facewhoee lower :portion-alias limi-ted zsuphme-rgence .in liquid hibricant, of a .stationary memberdisposed in plowingrelationto thelubriCmt-.Set m1119- tion by said rotating element, for the upward deliection of said lubricant to the unsubmerged portions of the annular face of said rotating element.

9. In apparatus for the lubrication of vertically disposed gears, the combination of a vertically disposed gear having tooth faces radiating :trom its axis, a container for a liquid lubricant, the normal level of lubricant therein being such as to only partly submerge the gear teeth, means for rotating the gear and causing a How of lubricant in the container and an elevated obstruction in the path of flow of the lubricant to intercept and raise the flowing lubricant on the gear teeth and lubricate the latter.

, 10. The combination With a bevel gear, rotatable on a substantially horizontal axis and having limited submergenee at its lower portion in a lubricant supply, so that only the outer portions of its teeth in the Zone of submergence are carried below the lubricant level, of a member in said zone of submergence adjacent the gear teeth against Which the lubricant set in motion by said teeth accumulates, said member inclining upwardly above the lubricant level, whereby the accumulating lubricant is elevated into contact with the unsubmerged tooth portions.

FRANK P. DAHLSTROM. 

